Other than our home planet, conditions in the Solar System can get pretty extreme. Take our own moon — daytime temperatures can climb to 260 degrees Fahrenheit, while nighttime temps can dip to -280 F. And yet…

On July 16, 2022, a team of scientists announced they’ve found pits and caves on the moon that have a permanent temperature of 63 F. 

How can this be? Remember that the moon’s mares or “seas” were originally lava flows that have solidified into plains. Rivers of lava can carve out pathways underneath flows, creating lava tubes (which can also form when the exterior crusts solidify). Beginning in 2009, NASA’s Lunar Reconnaissance Orbiter (LRO) has found more than 200 pits on the moon, and about 16 of the pits appear to be collapsed lava tubes.

When analyzing the data, they found two of the most prominent pits have visible overhangs, clearly leading to some sort of cave or void. Fortunately, the LRO has a thermal camera that can check the temperatures within the pits compared to the surface. Using computer modeling, the temperature changes in the pit were tracked over time. They found the temperatures in the shadows remained relatively stable at about 63 F.

The key to this constant temperature appears to be the overhangs.  They keep the shadowy places from getting too hot during the day and from having heat escape at night.

So as inhospitable as the moon is, there still may be some comfortable locations.